Abstract: The bond strength between a sulphur-vulcanisable rubber and a metal, especially brass, is increased by using as bonding promoter an organic substance containing one or more groups of the formula --S--SO.sub.2 R where R represents (a) a radical --OM where M is a monovalent metal, the equivalent of a multivalent metal, a monovalent ion derived by the addition of a proton to a nitrogeneous base or the equivalent of a multivalent ion derived by the addition of two or more protons to a nitrogeneous base, or (b) an organic radical. Preferred promoters include sodium, zinc, nickel and cobalt organothiosulphates.

Abstract: Additives for rubber compositions, giving vulcanisates having improved retention of optimum physical properties, are polymeric trithiocarbonates having a structure comprising repeating units of the formula ##STR1## where R is an organic bridging group, e.g. an alkylene group.

Abstract: Additives for rubber compositions, giving vulcanizates having improved retention of optimum physical properties, are compounds having the formula R--S--B--S--R where B is an organic bridging group and R is an electron-withdrawing group, for example CN, CCl.sub.3, a radical containing an activated methylene group linked to the sulphur atom or the enolic tautomer of a keto-activated methylene group. Also useful as stabilizing agents are oligomeric analogues of such compounds.

Abstract: Compounds containing an organic thiosulphate anion and cationic nickel or cobalt in association with an amine, are useful in increasing the bond strength between metal, especially brass, and vulcanized rubber. Typical complexes are those where the anion is dodecylthiosulphate or hexamethylenebis(thiosulphate), and the amine is ethylenediamine or N-benzyl-N-t-octylamine.

Abstract: Additives for rubber compositions, giving vulcanizates having improved retention of optimum physical properties, are compounds having the formula R-S-B-S-R where B is an organic bridging group and R is an electron-withdrawing group, for example CN, CCl.sub.3, a radical containing an activated methylene group linked to the sulphur atom or the enolic tautomer of a keto-activated methylene group. Also useful as stabilizing agents are oligomeric analogues of such compounds.

Abstract: Additives for rubber compositions, giving vulcanisates having improved retention of optimum physical properties, are compounds containing two or more groups of the formula --S--SO.sub.2 R linked by an organic bridging group, or polymers containing two or more groups of the formula --S--SO.sub.2 R attached to an organic polymer chain, where R represents (a) a radical OM where M is a monovalent metal, the equivalent of a multivalent metal, a monovalent in derived by the addition of a proton to a nitrogenous base, or the equivalent of a multivalent ion derived by the addition of two or more protons to a nitrogenous base, or (b) an organic radical selected from aliphatic, cycloaliphatic, aromatic and heterocyclic radicals, and radicals which are combinations of any two or more such radicals.

Abstract: The bond strength between a sulphur-vulcanizable rubber and a metal, especially brass, is increased by using as bonding promoter a compound having the formula R--(CH.sub.2).sub.a --S.sub.2 O.sub.3.sup.- M.sup.+ or a hydrate thereof, where a has an integral value of at least 1, and where (i) M.sup.+ represents a sodium ion or an equivalent of a divalent nickel or cobalt ion and R represents hydroxy, cyano, chlorophenyl, fluorophenyl, nitrophenyl, alkoxyphenyl, alkylphenyl, dialkylphenyl, arylphenyl, naphthyl, alkylnaphthyl, benzoyl, phenoxy, halophenoxy, phthalimido, a group having the formula R.sup.2 CONH--, R.sup.2 NHCO--, where R.sup.2 is an alkyl or aryl radical, .sup.+ MOOC, or 2,4-dihydroxy-6-pyrimidyl (or its keto-form equivalent) or (ii) M .sup.+ is absent and R represents a grouping .sup.+ H.sub.3 N--.

Abstract: Additives for rubber compositions, giving vulcanizates having improved retention of optimum physical properties, are polymeric trithiocarbonates having a structure comprising repeating units of the formula ##STR1## where R is an organic bridging group, e.g. an alkylene group.

Abstract: The bond strength between a sulphur-vulcanizable rubber and a metal, especially brass, is increased by using as bonding promoter an organic substance containing one or more groups of the formula --S--SO.sub.2 R where R represents (a) a radical --OM where M is a monovalent metal, the equivalent of a multivalent metal, a monovalent ion derived by the addition of a proton to a nitrogeneous base or the equivalent of a multivalent ion derived by the addition of two or more protons to a nitrogeneous base, or (b) an organic radical. Preferred promoters include sodium, zinc, nickel and cobalt organothiosulphates.

Abstract: Additives for rubber compositions, giving vulcanizates having improved retention of optimum physical properties, are compounds containing two or more groups of the formula --S--SO.sub.2 R linked by an organic bridging group, or polymers containing two or more groups of the formula --S--SO.sub.2 R attached to an organic polymer chain, where R represents (a) a radical OM where M is a monovalent metal, the equivalent of a multivalent metal, a monovalent ion derived by the addition of a proton to a nitrogenous base, or the equivalent of a multivalent ion derived by the addition of two or more protons to a nitrogenous base, or (b) an organic radical selected from aliphatic, cycloaliphatic, aromatic and heterocyclic radicals, and radicals which are combinations of any two or more such radicals.

Abstract: Additives for rubber compositions, giving vulcanisates having improved retention of optimum physical properties, are compounds containing two or more groups of the formula --S--SO.sub.2 R linked by an organic bridging group, or polymers containing two or more groups of the formula --S--SO.sub.2 R attached to an organic polymer chain, where R represents (a) a radical OM where M is a monovalent metal, the equivalent of a multivalent metal, a monovalent ion derived by the addition of a proton to a nitrogenous base, or the equivalent of a multivalent ion derived by the addition of two or more protons to a nitrogenous base, or (b) an organic radical selected from aliphatic, cycloaliphatic, aromatic and heterocyclic radicals, and radicals which are combinations of any two or more such radicals.